[R] help.start() caused high CPU loading

[Jinsong Zhao]

On 2020/4/28 3:40, Abby Spurdle wrote:
>>> (3) If (2) true, how much CPU is R using?
>> 0%.
> 
>>> (4) If (3) is zero, what processes are using the CPU the most?
>> In such case, almost every processes is using the CPU in a very low
>> percentage, i.e., 1% or below. I don't recognized those processes.
>> Now, I invoke help.start(), about 25% of CPU loading is used by R. Quit
>> from R, the CPU loading go back to idle.
> 
> Is R using 0% or 25%?
> 
> Again, if R was using 25% while showing the prompt and waiting for
> user input, that would be a bug in R.

25% CPU is used by R. And R shows the prompt and waits for user input.

Here is a report of the CPU usage by Rgui from Windows command line:
C:\Users\Jinso>typeperf "\Process(Rgui)\% Processor Time" -si 5
....
"04/28/2020 13:31:05.895","-1"
"04/28/2020 13:31:10.915","0.622494"
"04/28/2020 13:31:15.925","0.000000"
"04/28/2020 13:31:20.935","0.000000"
"04/28/2020 13:31:25.945","0.000000"
"04/28/2020 13:31:30.965","2.801177"
"04/28/2020 13:31:35.975","37.418638"
"04/28/2020 13:31:40.982","100.159072"
"04/28/2020 13:31:45.987","99.887614"
"04/28/2020 13:31:50.992","99.899896"
"04/28/2020 13:31:55.999","119.270784"
"04/28/2020 13:32:01.002","299.014789"
"04/28/2020 13:32:06.007","299.666184"
"04/28/2020 13:32:11.015","294.905707"
"04/28/2020 13:32:16.019","299.755921"
"04/28/2020 13:32:21.025","299.924392"
"04/28/2020 13:32:26.030","296.594191"
"04/28/2020 13:32:31.048","298.195791"
"04/28/2020 13:32:36.054","292.362986"
"04/28/2020 13:32:41.064","292.503832"
"04/28/2020 13:32:46.068","301.650976"
...
...

At about 10", I start Rgui, the CPU usage is about 0.5~1% (The second 
column number may be divided by 4).

At about 35", I call help.start() from menu of Rgui, you may notice that 
CPU usage increased to about 25%.

At about 55", I click on the ``Packages'' link in the browser. The CPU 
usage increased to about 70-75%, and closing browser does not have any 
effects on the CPU usage of R.


> 
> Or do you mean R is using 0% and total CPU usage *temporarily*
> increases 25% *while* R is running?
> If so, this could be the result of some security feature...? not sure
> because this is outside my area...
> 
> I just found the following feature.
> If you open powershell, one can run: ps | sort -desc cpu
> 
> This could be used if you want to show people what's happening.
> 
> PS C:\Users\spurdle> ps | sort -desc cpu
> 
> Handles  NPM(K)    PM(K)      WS(K)     CPU(s)     Id  SI ProcessName
> -------  ------    -----      -----     ------     --  -- -----------
>      625      28   108940     111644   4,900.52   8176   0 audiodg
>      794      38   234888     177924      62.13   8652  19 chrome
>     1673      71    84372     147628      61.97  10304  19 chrome
>      330      25   100096     146968      55.80   1052  19 chrome
>      391      26   141928     181264      35.27   6884  19 chrome
>      291      20    46676      80472      15.25   5352  19 chrome
>     2351      79    58404     107276      13.33   6940  19 explorer
>      443      22    17916      34764      12.17   7196  19 chrome
>     1331      90   107628      87596      10.86   9432  19 SearchUI
>      671      41    56184      70320       9.94  10420  19 powershell
>      362      24    51984      91568       9.06   4360  19 chrome
>     1129     107   206988      31852       7.17   6740  19 SkypeApp
>      696      40    26764      45620       5.33   4348  19
> Lenovo.Modern.ImController.PluginHost.Device
>      256      20    56860      84372       5.17   1660  19 chrome
>      284      18    34532      62112       5.13   1212  19 chrome
>      291      19     7048      16360       4.30   1476  19 chrome
> 
> Diverging, I can't figure out how to permanently stop Lenovo and Skype
> processes, or why chrome (and edge) need so many copies of
> themselves...
> Anyway, the plan is to shift to Debian or OpenIndianna, and run
> ReactOS via virtualization...
>